What is an unconformity? a. evidence of past life b. all the time passed since the origin of earth c. a division of strata that can have multiple layers d. an erosional surface representing a gap of time in the geological record

Radiometric dating is used to tell the absolute age of materials by studying the decay rate of radioactive isotopes. the decay rates of isotopes are constant and are expressed as .

18. which statement about cancer is true?

16 select the correct answer from each drop-down menu. sharks, whales, and dolphins share similar features such as body shape and the position of fins. hoy while whales and dolphins have lungs. these differences indicate that the organisms share a comme whales also possess a vestigial pelvic bone. the presence of the pelvis bone may indicate that whales reset next